Results 1 to 12 of 12

Thread: ecu location and codes

  1. #1
    DX User l75eya's Avatar
    Join Date
    Jun 2008
    Vehicle
    1987 Honda Accord DX Hatch
    Location
    Union City, New Jersey
    Posts
    36

    Question ecu location and codes

    Could anybody tell me where the ecu is in an 87 hatch, and how I can put it into diagnostic mode? I had a nissan that had a small screw on the ecu and if it was turned in one direction it would throw the ecu into diag. mode and blink out the code number in the dash, is there a way to do that with these cars too, or do I have to go out and buy a diag. tool to hook up to it?



  2. #2


    Join Date
    Sep 2004
    Vehicle
    ???? ????? ???? ?? ???
    Location
    On Hiatus
    Posts
    4,277

    Re: ecu location and codes

    1.5 Seconds using the search and I had this:

    Quote Originally Posted by shepherd79
    How to check your ECU codes:
    1. move driver seat all the way forward.
    2. locate the box on the floor.
    3. locate the small plastic window and pop it open.
    4. turn the ignition on.
    5. count how many times the light blinks.
    6. refer to the table below.

    ECU CODES for 86-89 accord and 85-89 prelude

    Ok I think we finally got this fixed now.. These are the correct codes..

    00 LED FLASH(s) ECU

    01 LED FLASH(s) 85-98 Accord
    Oxygen Sensor "A" (Primary)
    defective circuit or unplugged / defective sensor

    02 LED FLASH(s) 85-89 Accord
    Oxygen Sensor "B"
    defective circuit or unplugged / defective sensor

    03 LED FLASH(s) 85-98 Accord
    MAP Sensor (Manifold Absolute Pressure)
    defective circuit or unplugged / defective sensor

    04 LED FLASH(s) Crank Angle

    05 LED FLASH(s) 85-98 * Accord
    MAP Sensor (Manifold Absolute Pressure)
    mechanical problem / disconnected piping
    * exc. 94-95

    06 LED FLASH(s) 85-98 Accord
    ECT Sensor (Engine Coolant Temperature)
    defective circuit or unplugged / defective sensor

    07 LED FLASH(s) 85-98 Accord
    TP Sensor (Throttle Position)
    defective circuit or unplugged / defective sensor

    08 LED FLASH(s) 85-98 Accord
    TDC Sensor (Top Dead Center)
    defective circuit or unplugged / defective sensor

    09* LED FLASH(s) 85-98** Accord
    CYP Sensor (Cylinder)
    defective circuit or unplugged / defective sensor
    * not a valid code for any throttle body injection Hondas
    ** not a valid code for V-6 engines

    10 LED FLASH(s) 85-98 Accord
    IAT Sensor (Intake Air Temperature)
    defective circuit or unplugged / defective sensor

    12 LED FLASH(s) 85-98 Accord
    EGR Lift Sensor (Exhaust Gas Recirculation)
    defective circuit or unplugged / defective sensor

    13 LED FLASH(s) 85-98 Accord
    BARO Sensor (Atmospheric Pressure)
    defective circuit or unplugged / defective sensor

    14 LED FLASH(s) 88-98 Accord
    IAC Valve (Idle Air Control)
    defective circuit or unplugged / defective sensor
    IAC VALVE HELP

    15 LED FLASH(s) Ignition output signal

    16 LED FLASH(s) fuel injector

    17 LED FLASH(s) 88-98 Accord
    VSS (Vehicle Speed Sensor)
    defective circuit or unplugged / defective sensor
    2004-2011?

  3. #3
    LX User greentee76's Avatar
    Join Date
    Feb 2008
    Vehicle
    1988 Honda Accord LX 5sp
    Location
    Kalamazoo,MI
    Posts
    422

    Re: ecu location and codes

    DX? Carbed?
    If you are carbed there is no onboad diagnostic.
    88 LX 5spd l 32/36 weber l KYB GR-2's l Refreshed A20A3 engine l

  4. #4
    DX User l75eya's Avatar
    Join Date
    Jun 2008
    Vehicle
    1987 Honda Accord DX Hatch
    Location
    Union City, New Jersey
    Posts
    36

    Re: ecu location and codes

    Quote Originally Posted by forrest89sei View Post
    1.5 Seconds using the search and I had this:
    Figures, I spent about 15 minutes trying to find anything and looked through each "How-to" sub-forum to no avail, nonetheless, thank you very much for posting that for me = ).

  5. #5
    DX User l75eya's Avatar
    Join Date
    Jun 2008
    Vehicle
    1987 Honda Accord DX Hatch
    Location
    Union City, New Jersey
    Posts
    36

    Re: ecu location and codes

    Quote Originally Posted by greentee76 View Post
    DX? Carbed?
    If you are carbed there is no onboad diagnostic.
    Does this mean that there's no blinking light on the ecu itself under the driver's seat as there is said to be in the how to? I ran out and popped the little cap down and turned the ignition on and couldn't see any lights blinking in that box or anything. Do you think if the ECU were not functional at all, my car would still run? My driver's side floor got flooded and since then the car has been running like shit.

  6. #6

    nfs480's Avatar
    Join Date
    Nov 2007
    Vehicle
    1989 Honda Accord SE-i
    Location
    Rogers, MN, USA
    Posts
    555

    Re: ecu location and codes

    If you have the DX trim then your car doesn't have an ECU at all. That's because you have the carbureted version of the engine and not the fuel-injected.

  7. #7


    Join Date
    Sep 2004
    Vehicle
    ???? ????? ???? ?? ???
    Location
    On Hiatus
    Posts
    4,277

    Re: ecu location and codes

    Well the DX has a ECU, it's just not like the ECU a EFI Accord has.

    If your ECU is messed up let me know, I have a working one for sale
    2004-2011?

  8. #8
    DX User l75eya's Avatar
    Join Date
    Jun 2008
    Vehicle
    1987 Honda Accord DX Hatch
    Location
    Union City, New Jersey
    Posts
    36

    Re: ecu location and codes

    Quote Originally Posted by nfs480 View Post
    If you have the DX trim then your car doesn't have an ECU at all. That's because you have the carbureted version of the engine and not the fuel-injected.
    Shit, so that gray box that's under my driver's side seat is just empty? Is there anything in that thing that affects the engine because I've been clueless as to why my car has been running like hell and this was my first break as to an idea what happened =(

  9. #9


    Join Date
    Sep 2004
    Vehicle
    ???? ????? ???? ?? ???
    Location
    On Hiatus
    Posts
    4,277

    Re: ecu location and codes

    Quote Originally Posted by l75eya View Post
    Shit, so that gray box that's under my driver's side seat is just empty? Is there anything in that thing that affects the engine because I've been clueless as to why my car has been running like hell and this was my first break as to an idea what happened =(
    It's not empty, it runs solenoids and other things related to the carb on these cars, Unlike the EFI ECU it doesn't have a diagnostic mode
    2004-2011?

  10. #10
    DX User l75eya's Avatar
    Join Date
    Jun 2008
    Vehicle
    1987 Honda Accord DX Hatch
    Location
    Union City, New Jersey
    Posts
    36

    Re: ecu location and codes

    Quote Originally Posted by forrest89sei View Post
    It's not empty, it runs solenoids and other things related to the carb on these cars, Unlike the EFI ECU it doesn't have a diagnostic mode
    So it's safe to say that if this big gray box under my seat happened to get....really wet due to driving in heavy rain for over an hour on the highway with a big ass hole in the rear-driver's side wheel well that led to there being about 3 - 4 inches of water on the floor in the back, that could possibly be the reason my car is running horribly and won't idle and whatnot?

    I'm getting the feeling that this is probably the problem but just for a reality check, I'd really like to have it all spelled out nice and clear to be confirmed, because it's been over a week of messing around with the idle, air/fuel, vacuum advance, etc, etc and it's been driving me crazy.
    Wanna say thanks a lot for the feedback as well, I've been reading on this forum for months and just recently posted a first thread, I've found tons of insightful info on here! 3g ftw!
    Thx

  11. #11
    LX User greentee76's Avatar
    Join Date
    Feb 2008
    Vehicle
    1988 Honda Accord LX 5sp
    Location
    Kalamazoo,MI
    Posts
    422

    Re: ecu location and codes

    I was trying to find a writeup that lostforawhile did on this but can't seem to find it. SO I will try my best to explain the theory of how this system works.
    First of all Honda set up the carb to run rich as a base. The solenoid control unit(under the drivers seat) take electrical readings and open and close solenoids on the intake manifold(white saucer looking deals) to lean out the mixture when appropriate. If the box under the seat is bad generally you will revert to a rich situation.
    The best source of info on the feedback carb system that I have found (recommended by lostforawile) is chilton book # 6980 Honda 1973 to 1988.
    Hope this info is helpful.
    By the way if you do decide you need a new box I would take Forrest up on his, I have alot of his parts on my car now, and he is great to deal with.
    Good luck!
    88 LX 5spd l 32/36 weber l KYB GR-2's l Refreshed A20A3 engine l

  12. #12
    LX User greentee76's Avatar
    Join Date
    Feb 2008
    Vehicle
    1988 Honda Accord LX 5sp
    Location
    Kalamazoo,MI
    Posts
    422

    Re: ecu location and codes

    Just to clarify:
    The big grey box you see under the seat is just a cover the solenoid control lives under it.
    88 LX 5spd l 32/36 weber l KYB GR-2's l Refreshed A20A3 engine l

Similar Threads

  1. location of ?
    By FORFREE in forum 3geez Accords
    Replies: 7
    Last Post: 01-14-2006, 06:26 PM
  2. ecu location
    By 89AccordLvr in forum 3geez Accords
    Replies: 2
    Last Post: 01-21-2004, 04:22 PM
  3. different sunroof location
    By 89AccordHatch in forum Interior & Exterior Care
    Replies: 33
    Last Post: 08-10-2003, 09:26 AM
  4. Amp location
    By Mac in forum Interior & Exterior Care
    Replies: 15
    Last Post: 07-11-2003, 07:12 PM
  5. Location of Map Sensor
    By jteuton in forum 3geez Accords
    Replies: 6
    Last Post: 10-25-2002, 10:08 PM

Bookmarks

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •